While the methods, compositions and materials presented herein may be used in a variety of applications, they were specifically developed with respect to orthopedic casting tapes. Therefore, as background, characterizations of technology relating to orthopedic casting tapes and problems overcome by the present invention are provided.
Orthopedic casting tapes have been produced using curable resins coated on a substrate. Typically, the casting tape is stored as a roll, in a water impermeable storage pouch, until needed for use. It is then removed from the pouch, cut to length, if necessary, and soaked with water. Generally, the tape includes a resin therein which is water-curable, and thus shortly after the tape is dipped in water it begins to cure and harden. The medical personnel, applying the tape to a patient, apply the casting tape immediately after it has been soaked with water. Generally, resin materials are chosen which will begin to set within a few minutes after the soaking with water, and which will harden sufficiently to be weight bearing within about 15 to 30 minutes.
Examples of such orthopedic casting tapes are described in U.S. Pat. Nos. 4,667,661 and 4,774,937 to Scholz et al., the disclosures of which are incorporated herein by reference. U.S. Pat. Nos. "661 and "937 are both owned by Minnesota Mining and Manufacturing Company of St. Paul, Minn., the assignee of the present invention.
Orthopedic casting tapes of the type briefly described above are commercially available. For example, Scotchcast.RTM.2 casting tape; Scotchcast.RTM. PLUS casting tape and Scotchcast.RTM.3 casting tape, are available from 3M Company.
In general, it is desired that the casting tape be constructed from a fabric or substrate which is relatively stretchable; i.e., which has an extensibility of at least about 15 to 25 percent, preferably at least about 20 percent, once coated with the uncured resin. This will facilitate fitting the casting tape around contoured portions of the body, such as the heel, knee or elbow. A preferred fiber material from which such stretchable casting tapes can be formed is fiberglass. Fiberglass woven or knitted substrates usable in casting tapes such as those of U.S. Pat. Nos. "661 and "937 include the knitted substrate of Scotchcast.RTM. PLUS casting tape, which tape is available from 3M Company, St. Paul, Minn. Other useable materials include knits having elastomeric yarns, such as Deltalight Conformable (Johnson and Johnson). A resin-coated extensible heat-set fiberglass knit tape, of a type useable in applications of concern herein, is described in U.S. Pat. No. 4,609,578, incorporated herein by reference.
As indicated generally above, typical orthopedic casting tapes comprise a substrate having a curable resin coated thereon. The resin generally includes such additives as lubricants and defoaming agents therein. The lubricants will facilitate unrolling, application and molding of the orthopedic casting tape, without the resin (prior to setting) interfering. The defoaming agents act to increase cast strength and porosity.
A market demand has arisen for the provision of items such as orthopedic casting tapes which are provided with a decorative presentation. Decorations desirable for such constructions include, for example, solid colors, prints and multicolored decorations. A need has therefore arisen for the development of methods and materials for generating such decorations on fabric materials such as those used in preferred orthopedic casting tapes.